A preparation of a racemic mixture of a 2-amino-.omega.-oxoalkanoic acid derivative of formula 1 is described in Biorg. & Med. Chem. (1995) 1237-1240. However, the preparation method described therein proceeds via an 8-step process, starting from 3,4-dihydro-2H-pyran, with various protection and de-protection steps and is hence very laborious.